Brachial plexopathy following stereotactic body radiation therapy in apical lung malignancies: A dosimetric pooled analysis of individual patient data.

BACKGROUND AND OBJECTIVES: The aim of this study is to establish dosimetric constraints for the brachial plexus at risk of developing grade ≥ 2 brachial plexopathy in the context of stereotactic body radiation therapy (SBRT). PATIENTS AND METHODS: Individual patient data from 349 patients with 356 apical lung malignancies who underwent SBRT were extracted from 5 articles. The anatomical brachial plexus was delineated following the guidelines provided in the atlases developed by Hall, et al. and Kong, et al.. Patient characteristics, pertinent SBRT dosimetric parameters, and brachial plexopathy grades (according to CTCAE 4.0 or 5.0) were obtained. Normal tissue complication probability (NTCP) models were used to estimate the risk of developing grade ≥ 2 brachial plexopathy through maximum likelihood parameter fitting. RESULTS: The prescription dose/fractionation schedules for SBRT ranged from 27 to 60 Gy in 1 to 8 fractions. During a follow-up period spanning from 6 to 113 months, 22 patients (6.3 %) developed grade ≥2 brachial plexopathy (4.3 % grade 2, 2.0 % grade 3); the median time to symptoms onset after SBRT was 8 months (ranged, 3-54 months). NTCP models estimated a 10 % risk of grade ≥2 brachial plexopathy with an anatomic brachial plexus maximum dose (Dmax) of 20.7 Gy, 34.2 Gy, and 42.7 Gy in one, three, and five fractions, respectively. Similarly, the NTCP model estimates the risks of grade ≥2 brachial plexopathy as 10 % for BED Dmax at 192.3 Gy and EQD2 Dmax at 115.4 Gy with an α/ß ratio of 3, respectively. Symptom persisted after treatment in nearly half of patients diagnosed with grade ≥2 brachial plexopathy (11/22, 50 %). CONCLUSIONS: This study establishes dosimetric constraints ranging from 20.7 to 42.7 Gy across 1-5 fractions, aimed at mitigating the risk of developing grade ≥2 brachial plexopathy following SBRT. These findings provide valuable guidance for future ablative SBRT in apical lung malignancies.

Dosimetric analysis of brachial plexopathy after stereotactic body radiotherapy: Significance of organ delineation.

OBJECTIVES: Examine the significance of contouring the brachial plexus (BP) for toxicity estimation and select metrics for predicting radiation-induced brachial plexopathy (RIBP) after stereotactic body radiotherapy. MATERIALS AND METHODS: Patients with planning target volume (PTV) ≤ 2 cm from the BP were eligible. The BP was contoured primarily according to the RTOG 1106 atlas, while subclavian-axillary veins (SAV) were contoured according to RTOG 0236. Apical PTVs were classified as anterior (PTV-A) or posterior (PTV-B) PTVs. Variables predicting grade 2 or higher RIBP (RIBP2) were selected through least absolute shrinkage and selection operator regression and logistic regression. RESULTS: Among 137 patients with 140 BPs (median follow-up, 32.1 months), 11 experienced RIBP2. For patients with RIBP2, the maximum physical dose to the BP (BP-Dmax) was 46.5 Gy (median; range, 35.7 to 60.7 Gy). Of these patients, 54.5 % (6/11) satisfied the RTOG limits when using SAV delineation; among them, 83.3 % (5/6) had PTV-B. For patients with PTV-B, the maximum physical dose to SAV (SAV-Dmax) was 11.2 Gy (median) lower than BP-Dmax. Maximum and 0.3 cc biologically effective doses to the BP based on the linear-quadratic-linear model (BP-BEDmax LQL and BP-BED0.3cc LQL, α/ß = 3) were selected as predictive variables with thresholds of 118 and 73 Gy, respectively. CONCLUSION: Contouring SAV may significantly underestimate the RIBP2 risk in dosimetry, especially for patients with PTV-B. BP contouring indicated BP-BED0.3cc LQL and BP-BEDmax LQL as potential predictors of RIBP2.

Reirradiation with stereotactic body radiotherapy for primary or secondary lung malignancies: Tumor control probability and safety analyses.

BACKGROUND: Reirradiation with stereotactic body radiotherapy (SBRT) for patients with primary or secondary lung malignancies represents an appealing definitive approach, but its feasibility and safety are not well defined. The purpose of this study was to investigate the tumor control probability (TCP) and toxicity for patients receiving reirradiation with SBRT. PATIENTS AND METHODS: Eligible patients with recurrence of primary or secondary lung malignancies from our hospital were subjected to reirradiation with SBRT, and PubMed- and Embase-indexed articles were reviewed. The patient characteristics, pertinent SBRT dosimetric details, local tumor control, and toxicities were extracted. The logistic dose-response models were compared for TCP and overall survival (OS) in terms of the physical dose and three-, four-, and five-fraction equivalent doses. RESULTS: The data of 17 patients from our hospital and 195 patients extracted from 12 articles were summarized. Reirradiation with SBRT yielded 2-year estimates of 80% TCP for doses of 50.10 Gy, 55.85 Gy, and 60.54 Gy in three, four, and five fractions, respectively. The estimated TCP with common fractionation schemes were 50%, 60%, and 70% for 42.04 Gy, 47.44 Gy, and 53.32 Gy in five fractions, respectively. Similarly, the 2-year estimated OS was 50%, 60%, and 70% for 41.62 Gy, 46.88 Gy, and 52.55 Gy in five fractions, respectively. Central tumor localization may be associated with severe toxicity. CONCLUSIONS: Reirradiation with SBRT doses of 50-60 Gy in 3-5 fractions is feasible for appropriately selected patients with recurrence of peripheral primary or secondary lung malignancies, but should be carefully considered for centrally-located tumors due to potentially severe toxicity. Further studies are warranted for optimal dose/fractionation schedules and more accurate selection of patients suitable for reirradiation with SBRT.

Risk-adapted stereotactic body radiotherapy for patients with cervical spinal metastases.

Owing to the complex anatomical structure and biomechanics, the current standard palliative treatments for cervical spinal metastases are associated with a high risk of recurrence and complications. Stereotactic body radiotherapy (SBRT) can provide radical dose to tumors while protecting normal organs to the maximum extent. However, the efficacy and safety of SBRT for cervical spinal metastases is not well characterized. Data from 71 patients with cervical spine metastases who were treated with SBRT using CyberKnife between 2006 and 2021 were obtained from our prospectively maintained database. Primary endpoint was pain response at 12 weeks following SBRT completion; secondary endpoints included local control (LC), overall survival (OS), and adverse events. Standard-risk patients were planned to receive 30 Gy (range 21-36) with median fractions of 3 (range 1-3) and high-risk patients 35 Gy (range 24-50) with median fractions of 5 (range 4-5) according to the spinal cord and esophagus dose constraints. The median follow-up time was 17.07 months (range 3.1-118.9). After 12 weeks of SBRT completion, 54 (98.2%) of 55 patients with baseline pain achieved pain response and 46 (83.6%) achieved complete pain response. LC rates were 93.1% and 90% at 1 year and 2 year, respectively. The 1-year and 2-year OS rates were 66.2% and 37.4%, respectively. Eight patients experienced grades 1-4 adverse events (six vertebral compression fracture [VCF], five of them had VCF before SBRT; and two hemiparesis). No grade 5 adverse events were observed. Therefore, risk-adapted SBRT for cervical spine metastases achieved high pain control and LC rates with acceptable adverse events.

The Epidemiology of Lung Metastases.

Introduction: Lung metastasis is usually associated with poor outcomes in cancer patients. This study was performed to characterize and analyze the population of patients with de novo (synchronous) lung metastases using the Surveillance, Epidemiology and End Results (SEER) database. Materials and Methods: Baseline characteristics of lung metastasis patients were obtained from SEER case listings. Incidence rates and counts of synchronous lung metastasis were also obtained using the SEER*Stat software. Survival outcomes were analyzed using univariate and multivariable Cox regressions, controlling for confounders. An alpha threshold of 0.05 was used for statistical significance and p-values were subject to correction for multiple comparisons. Results: The age-adjusted incidence rate of synchronous lung metastasis was 17.92 per 100,000 between 2010 and 2015. Synchronous lung metastases most commonly arose from primary lung cancers, colorectal cancers, kidney cancers, pancreatic cancers and breast cancers. During this time period, 4% of all cancer cases presented with synchronous lung metastasis. The percentage of patients presenting with synchronous lung metastasis ranged from 0.5% of all prostate cancers to 13% of all primary lung cancers. The percentage of all cancer cases presenting with synchronous lung metastasis increased over time. De novo metastatic patients with lung metastases had worse overall survival [hazard ratio = 1.22 (1.21-1.23), p < 0.001] compared to those with only extrapulmonary metastases, controlling for potential confounders. Conclusions: Synchronous lung metastasis occurs frequently and is an independent predictors of poor patient outcomes. As treatment for lung metastases becomes more complicated, patients with synchronous lung metastasis represent a high-risk population.

Safety and Survival Rates Associated With Ablative Stereotactic Radiotherapy for Patients With Oligometastatic Cancer: A Systematic Review and Meta-analysis.

IMPORTANCE: The oligometastatic paradigm postulates that patients with a limited number of metastases can be treated with ablative local therapy to each site of disease with curative intent. Stereotactic ablative radiotherapy (SABR) is a radiation technique that has become widely used in this setting. However, prospective data are limited and are mainly from single institutional studies. OBJECTIVE: To conduct a meta-analysis to characterize the safety and clinical benefit of SABR in oligometastatic cancer. DATA SOURCES: A comprehensive search was conducted in PubMed/MEDLINE, Embase, Cochrane Database of Systematic Reviews, and Cumulative Index to Nursing and Allied Health Literature on December 23, 2019, that included prospective clinical trials and review articles that were published within the past 15 years. STUDY SELECTION: Inclusion criteria were single-arm or multiarm prospective trials including patients with oligometastatic cancer (ie, ≤5 sites of extracranial disease), and SABR was administered in less than or equal to 8 fractions with greater than or equal to 5 Gy/fraction. DATA EXTRACTION AND SYNTHESIS: The Population, Intervention, Control, Outcomes and Study Design; Preferred Reporting Items for Systematic Reviews and Meta-analyses; and Meta-analysis of Observational Studies in Epidemiology methods were used to identify eligible studies. Study eligibility and data extraction were reviewed by 3 authors independently. Random-effects meta-analyses using the Knapp-Hartung correction, arcsine transformation, and restricted maximum likelihood method were conducted. MAIN OUTCOMES AND MEASURES: Safety (acute and late grade 3-5 toxic effects) and clinical benefit (1-year local control, 1-year overall survival, and 1-year progression-free survival). RESULTS: Twenty-one studies comprising 943 patients and 1290 oligometastases were included. Median age was 63.8 years (interquartile range, 59.6-66.1 years) and median follow-up was 16.9 months (interquartile range, 13.7-24.5 months). The most common primary sites were prostate (22.9%), colorectal (16.6%), breast (13.1%), and lung (12.8%). The estimate for acute grade 3 to 5 toxic effect rates under the random-effects models was 1.2% (95% CI, 0%-3.8%; I2 = 50%; 95% CI, 3%-74%; and τ = 0.20%; 95% CI, 0.00%-1.43%), and the estimate for late grade 3 to 5 toxic effects was 1.7% (95% CI, 0.2%-4.6%; I2 = 54%; 95% CI, 11%-76%; and τ = 0.25%; 0.01%-1.00%). The random-effects estimate for 1-year local control was 94.7% (95% CI, 88.6%-98.6%; I2 = 90%; 95% CI, 86%-94%; and τ = 0.81%; 95% CI, 0.36%-2.38%]). The estimate for 1-year overall survival was 85.4% (95% CI, 77.1%-92.0%; I2 = 82%; 95% CI, 71%-88%; and τ = 0.72%; 95% CI, 0.30%-2.09%) and 51.4% (95% CI, 42.7%-60.1%; I2 = 58%; 95% CI, 17%-78%; and τ = 0.20%; 95% CI, 0.02%-1.21%) for 1-year progression-free survival. CONCLUSIONS AND RELEVANCE: In this meta-analysis, SABR appears to be relatively safe in patients with oligometastatic cancer with clinically acceptable rates of acute and late grade 3 to 5 toxic effects less than 13% and with clinically acceptable rates of 1-year local control overall survival, and progression-free survival. These findings are hypothesis generating and require validation by ongoing and planned prospective clinical trials.

Risk-adapted stereotactic body radiation therapy for central and ultra-central early-stage inoperable non-small cell lung cancer.

To determine the therapeutic efficacy and safety of risk-adapted stereotactic body radiation therapy (SBRT) schedules for patients with early-stage central and ultra-central inoperable non-small cell lung cancer. From 2006 to 2015, 80 inoperable T1-2N0M0 NSCLC patients were treated with two median dose levels: 60 Gy in six fractions (range, 48-60 Gy in 4-8 fractions) prescribed to the 74% isodose line (range, 58%-79%) for central lesions (ie within 2 cm of, but not abutting, the proximal bronchial tree; n = 43), and 56 Gy in seven fractions (range, 48-60 Gy in 5-10 fractions) prescribed to the 74% isodose line (range, 60%-80%) for ultra-central lesions (ie abutting the proximal bronchial tree; n = 37) on consecutive days. Primary endpoint was overall survival (OS); secondary endpoints included progression-free survival (PFS), tumor local control rate (LC), and toxicity. Median OS and PFS were 64.47 and 32.10 months (respectively) for ultra-central patients, and not reached for central patients. Median time to local failure, regional failure, and any distant failures for central versus ultra-central lesions were: 27.37 versus 26.07 months, 20.90 versus 12.53 months, and 20.85 versus 15.53 months, respectively, all P < .05. Multivariate analyses showed that tumor categorization (ultra-central) and planning target volume ≥52.76 mL were poor prognostic factors of OS, PFS, and LC, respectively (all P < .05). There was one grade 5 toxicity; all other toxicities were grade 1-2. Our results showed that ultra-central tumors have a poor OS, PFS, and LC compared with central patients because of the use of risk-adapted SBRT schedules that allow for equal and favorable toxicity profiles.

Ablative Hypofractionated Radiation Therapy Enhances Non-Small Cell Lung Cancer Cell Killing via Preferential Stimulation of Necroptosis In Vitro and In Vivo.

PURPOSE: To investigate how necroptosis (ie, programmed necrosis) is involved in killing of non-small cell lung cancer (NSCLC) after ablative hypofractionated radiation therapy (HFRT). METHODS AND MATERIALS: Deoxyribonucleic acid damage, DNA repair, and the death form of NSCLC cells were assessed after radiation therapy. The overexpression and silencing of receptor-interacting protein kinases 3 (RIP3, a key protein involved activation of necroptosis)-stable NSCLC cell lines were successfully constructed. The form of cell death, the number and area of colonies, and the regulatory proteins of necroptosis were characterized after radiation therapy in vitro. Finally, NSCLC xenografts and patient specimens were used to examine involvement of necroptosis after ablative HFRT in vivo. RESULTS: Radiation therapy induced expected DNA damage and repair of NSCLC cell lines, but ablative HFRT at ≥10 Gy per fraction preferentially stimulated necroptosis in NSCLC cells and xenografts with high RIP3 expression, as characterized by induction and activation of RIP3 and mixed-lineage kinase domain-like protein and release of immune-activating chemokine high-mobility group box 1. In contrast, RNA interference of RIP3 attenuated ablative HFRT-induced necroptosis and activation of its regulatory proteins. Among central early-stage NSCLC patients receiving stereotactic body radiation therapy, high expression of RIP3 was associated with improved local control and progression-free survival (all P < .05). CONCLUSIONS: Ablative HFRT at ≥10 Gy per fraction enhances killing of NSCLC with high RIP3 expression via preferential stimulation of necroptosis. RIP3 may serve as a useful biomarker to predict favorable response to stereotactic body radiation therapy.

Targeting Myeloid-derived Suppressor Cells and Programmed Death Ligand 1 Confers Therapeutic Advantage of Ablative Hypofractionated Radiation Therapy Compared With Conventional Fractionated Radiation Therapy.

PURPOSE: Ablative hypofractionated radiation therapy (AHFRT) presents a therapeutic advantage compared with conventional fractionated radiation therapy (CFRT) for primary and oligometastatic cancers. However, the underlying mechanisms remain largely unknown. In the present study, we compared the immune alterations in response to AHFRT versus CFRT and examined the significance of immune regulations contributing to the efficacy of AHFRT. METHODS AND MATERIALS: We established subcutaneous tumors using syngeneic lung cancer and melanoma cells in both immunocompetent and immunocompromised mice and treated them with AHFRT and CFRT under the same biologically equivalent dose. RESULTS: Compared with CFRT, AHFRT significantly inhibited tumor growth in immunocompetent, but not immunocompromised, mice. On the cellular level, AHFRT reduced the recruitment of myeloid-derived suppressor cells (MDSCs) into tumors and decreased the expression of programmed death-ligand 1 (PD-L1) on those cells, which unlashed the cytotoxicity of CD8+ T cells. Through the downregulation of vascular endothelial growth factor (VEGF), AHFRT inhibited VEGF/VEGF receptor signaling, which was essential for MDSC recruitment. When combined with anti-PD-L1 antibody, AHFRT presented with greater efficacy in controlling tumor growth and improving mouse survival. By altering immune regulation, AHFRT, but not CFRT, significantly delayed the growth of secondary tumors implanted outside the irradiation field. CONCLUSIONS: Targeting MDSC recruitment and enhancing antitumor immunity are crucial for the therapeutic efficacy of AHFRT. When combined with anti-PD-L1 immunotherapy, AHFRT was more potent for cancer treatment.

Early postoperative radiotherapy is associated with improved outcomes over late postoperative radiotherapy in the management of completely resected (R0) Stage IIIA-N2 non-small cell lung cancer.

AIMS: The aim of this study was to evaluate the ideal timing of PORT in the management of completely resected (R0) Stage IIIA-N2 NSCLC. PATIENTS AND METHODS: Between January 2008 and December 2015, patients with known histologies of pathologic Stage IIIA-N2 NSCLC who underwent R0 resection and received PORT concurrent with or prior to two sequential cycles of chemotherapy ("early PORT") or with PORT administered after two cycles of chemotherapy ("late PORT") at multiple hospitals. The primary endpoint was OS; secondary end points included pattern of the first failure, LRRFS, and DMFS. Kaplan-Meier OS, LRRFS, and DMFS curves were compared with the log-rank test. Cox regression analysis was used to determine prognosticators for OS, LRRFS, and DMFS. RESULTS: Of 112 included patients, 41 (36.6%) and 71 (63.4%) patients received early PORT and late PORT, respectively. The median OS, LRRFS, and DMFS were longer for those who received early PORT than for those who received late PORT at the median follow-up of 29.6 months (all p < 0.05). Uni- and multi-variate analyses showed that number of POCT cycles and the combination schedule of PORT and POCT were independent prognostic factors for OS, LRRFS, and DMFS. CONCLUSIONS: Early PORT is associated with improved outcomes in pathologic Stage IIIA-N2 R0 NSCLC patients.

Sublobar resection is associated with improved outcomes over radiotherapy in the management of high-risk elderly patients with Stage I non-small cell lung cancer: a systematic review and meta-analysis.

BACKGROUND AND AIM: A matched-pair comparison was performed to compare the efficacy and safety of sublobar resection versus radiotherapy for high-risk elderly patients with Stage I non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: We searched the Cochrane Library, MEDLINE, CENTRAL, EMBASE and manual searches. The meta-analysis was performed to compare overall survival, pattern of failure, and toxicity among the homogeneous studies. Subdivided analyses were also performed. RESULTS: Sixteen studies containing 11540 patients were included in the meta-analysis. Among these studies, 9 were propensity-score matched (PSM) cohort studies, and 7 were cohort studies. Sublobar resection, compared with radiotherapy (either conventional fraction radiation therapy or stereotactic body radiation therapy), significantly improved the overall survival regardless in both PSM and non-PSM analyses (all p < 0.05). However, the difference in the pattern of failure and toxicity were not significant (all p > 0.05). CONCLUSIONS: Sublobar resection was associated with improved outcomes in high-risk elderly patients with Stage I NSCLC, which supports the need to compare both treatments in large prospective, randomized, controlled clinical trials.

Stereotactic body radiation therapy for patients with recurrent pancreatic adenocarcinoma at the abdominal lymph nodes or postoperative stump including pancreatic stump and other stump.

BACKGROUND AND AIM: The aim of this study is to evaluate the efficacy and safety of stereotactic body radiation therapy (SBRT) using CyberKnife in the treatment of patients with recurrent pancreatic adenocarcinoma at the abdominal lymph node or stump after surgery. PATIENTS AND METHODS: Between October 1, 2006 and May 1, 2015, patients with recurrent pancreatic adenocarcinoma at the abdominal lymph node or stump after surgery were enrolled and treated with SBRT at our hospital. The primary end point was local control rate after SBRT. Secondary end points were overall survival, time to symptom alleviation, and toxicity, assessed using the Common Terminology Criteria for Adverse Events version 4.0. RESULTS: Twenty-four patients with 24 lesions (17 abdominal lymph nodes and seven stumps) were treated with SBRT, of which five patients presented with abdominal lymph nodes and synchronous metastases in the liver and lung. The 6-, 12-, and 24-month actuarial local control rates were 95.2%, 83.8%, and 62.1%, respectively. For the entire cohort, the median overall survival from diagnosis and SBRT was 28.9 and 12.2 months, respectively. Symptom alleviation was observed in eleven of 14 patients (78.6%) within a median of 8 days (range, 1-14 days) after SBRT. Nine patients (37.5%) experienced Common Terminology Criteria for Adverse Events version 4.0 grade 1-2 acute toxicities; one patient experienced grade 3 acute toxicity due to thrombocytopenia. CONCLUSION: SBRT is a safe and effective treatment for patients with recurrent pancreatic adenocarcinoma at the abdominal lymph node or stump after surgery. Further studies are needed before SBRT can be recommended routinely.

Necroptosis in tumorigenesis, activation of anti-tumor immunity, and cancer therapy.

While the mechanisms underlying apoptosis and autophagy have been well characterized over recent decades, another regulated cell death event, necroptosis, remains poorly understood. Elucidating the signaling networks involved in the regulation of necroptosis may allow this form of regulated cell death to be exploited for diagnosis and treatment of cancer, and will contribute to the understanding of the complex tumor microenvironment. In this review, we have summarized the mechanisms and regulation of necroptosis, the converging and diverging features of necroptosis in tumorigenesis, activation of anti-tumor immunity, and cancer therapy, as well as attempts to exploit this newly gained knowledge to provide therapeutics for cancer.

Mesenchymal stem cells generate pericytes to promote tumor recurrence via vasculogenesis after stereotactic body radiation therapy.

BACKGROUND: Stereotactic body radiation therapy (SBRT) is postulated to enhance the recruitment of mesenchymal stem cells (MSCs) into the tumor microenvironment, which promote tumor recurrence. The aim of this study is to determine the molecular mechanisms behind SBRT stimulating MSC migration and differentiation. METHODS: In vitro, mediated factors and migrated MSCs (post-SBRT) were generated. In vivo, bone-marrow derived MSCs were identified and harvested from green fluorescent protein (GFP)-expressing transgenic male mice and transplanted into sub-lethally irradiated recipient female mice to establish a model of bone marrow transplantation. Lewis lung carcinoma and malignant melanoma-bearing recipient mice were treated with SBRT, 14 Gy/1 fraction. The migration and differentiation potential of MSCs were characterized. RESULTS: SBRT increased the release of stromal cell derived factor-1α (SDF-1α) and platelet-derived growth factor-B (PDGF-B) by tumor cells; these ligands bound to chemokine (C-X-C motif) receptor 4 (CXCR4) and platelet-derived growth factor receptor-ß (PDGFR-ß), respectively, on circulating bone marrow-derived MSCs, resulting in engraftment of the MSCs into the tumor parenchyma. The newly-homed MSCs differentiated into pericytes, which induced the tumor vasculogenesis, and promoted tumor regrowth. Targeted therapies, AMD3100 and imatinib abrogated MSC homing, vasculogenesis, and tumor regrowth. CONCLUSION: Bone-marrow derived MSCs migrate to the tumor parenchyma and differentiate into pericytes, inducing tumor vasculogenesis after SBRT, and promoting tumor recurrence. MSC migration and maturation may be abrogated with AMD3100 and imatinib. This novel treatment strategy warrants clinical investigation.

Stereotactic radiation therapy for oligometastases or oligorecurrence within mediastinal lymph nodes.

AIMS: This study evaluated the safety and efficacy of stereotactic radiation therapy (SRT) for the treatment of patients with oligometastases or oligorecurrence within mediastinal lymph nodes (MLNs) originating from different tumors. METHODS: Between October 2006 and May 2015, patients with MLN oligometastases or oligorecurrence were enrolled and treated with SRT at our hospital. The primary endpoint was MLN local control (LC). Secondary endpoints were time to symptom alleviation, overall survival (OS) after SRT, and toxicity using the Common Terminology Criteria for Adverse Events (CTCAE v4.0). RESULTS: Eighty-five patients with 98 MLN oligometastases or oligorecurrences were treated with SRT. For the entire cohort, the 1-year and 5-year actuarial LC rates were 97% and 77%, respectively. Of 53 symptomatic patients, symptom alleviation was observed in 47 (89%) after a median of 5 days (range, 3-30 days). The median OS was 27.2 months for all patients. For patients with non-small cell lung cancer, univariate and multivariate analyses revealed that a shorter interval between diagnosis of primary tumors and SRT and larger MLN SRT volume were associated with worse OS. CTCAE v4.0 ≥ Grade 3 toxicities occurred in six patients (7%), with Grade 5 in three patients (all with RT history to MLN station 7). CONCLUSIONS: SRT is a safe and efficacious treatment modality for patients with oligometastases or oligorecurrence to MLNs originating from different tumors, except for patients who received radiotherapy to MLN station 7. Further investigation is warranted to identify the patients who benefit most from this treatment modality.

The prognosis factor of adjuvant radiation therapy after surgery in uterine sarcomas.

OBJECTIVE: This retrospective study evaluated the role of adjuvant radiotherapy (AR) after surgery in patients with uterine sarcoma and analyzed the prognostic factors of local-regional failure-free survival (LRFFS) and overall survival (OS). PATIENTS AND METHODS: A study of a total of 182 patients with uterine sarcoma was conducted between June 1994 and October 2014. Adjuvant radiotherapy was defined as postoperative external beam radiation to the pelvis (30-50 Gray/10-25 fractions at five fractions/week). The primary end point was LRFFS, and the secondary end point was OS. Kaplan-Meier curves were compared using the log-rank test. Cox regression analyses were used to determine prognosticators for LRFFS and OS. RESULTS: The median follow-up time of all patients was 75 months, with a 5-year LRFFS of 62.1%. The 2-year and 5-year LRFFS rates were longer for those who received AR than for those who did not receive AR (83.4% vs 70.3%; 78% vs 55.3%; P=0.013). The 5-year OS of all patients was 56.2%, and no significant differences were observed in the 2-year and 5-year OS rates between these two groups (82.7% vs 71.4%; 64.1% vs 51.7%; P=0.067). Importantly, in patients with leiomyosarcoma, the 2-year and 5-year LRFFS and OS rates were longer for those who received AR than for those who did not receive AR (P=0.04 and P=0.02 for the 2-year and 5-year LRFFS, respectively). CONCLUSION: Patients with uterine sarcoma who were treated with AR after surgery demonstrated an improved LRFFS compared with those who were treated with surgery alone, especially those patients with leiomyosarcoma. Therefore, the role of personalized adjuvant radiation for patients with uterine sarcoma still requires further discussion.

Clinical evaluation of stereotactic radiation therapy for recurrent or second primary mediastinal lymph node metastases originating from non-small cell lung cancer.

AIMS: To evaluate the safety and efficacy of stereotactic radiotherapy (SRT, both stereotactic body RT [SBRT] and fractionated stereotactic RT [FSRT]) in the treatment of patients with recurrent or second primary mediastinal lymph node metastases (R/SP-MLNMs) originating from non-small cell lung cancer (NSCLC). METHODS: Between 10/2006 and 7/2013, patients with R/SP-MLNMs originating from NSCLC were enrolled and treated with SRT at our hospital; their data was stored in prospectively-collected database. The enrolled patients were divided into Group A (without prior RT) and Group B (with prior RT). The primary end-point was overall survival (OS). The secondary end-points were the MLNM local control (LC), the time to symptom alleviation, and toxicity using the Common Terminology Criteria for Adverse Events (CTCAE v4.0). RESULTS: Thirty-three patients were treated (16 in Group A with 19 R/SP-MLNMs and 17 in Group B with 17 R/SP-MLNMs). For the entire cohort, the median OS was 25.5 months with a median follow-up of 20.9 months (range, 3.2-82). The 1-year and 3-year actuarial LC rates were 100% and 86%, respectively. Symptom alleviation was observed in 52% of patients, after a median of 6 days (range, 3-18). CTCAE v4.0 ≥ Grade 3 toxicities occurred in 5 patients (15%; all in Group B); among them, Grade 5 in 2 patients. CONCLUSIONS: We recommend exercising extreme caution in using SRT for R/SP-MLNMs in patients who received prior RT (particularly to LN station 7). For patients without previous RT, SRT appears to be safe and efficacious treatment modality; prospective studies are warranted.

Multimodality therapy is recommended for limited-stage combined small cell esophageal carcinoma.

BACKGROUND AND AIM: Limited-stage combined small cell esophageal carcinoma (LS-C-SCEC) is a rare, poorly understood, underdiagnosed disease, with components of both small cell esophageal cancer and non-small cell esophageal cancer. We investigated the optimal treatment strategy and prognostic factors in patients with LS-C-SCEC. PATIENTS AND METHODS: LS-C-SCEC patients included in the analysis (from our hospital and the literature) were treated between January 1966 and December 2013. Patient treatment strategies included surgery (S), chemotherapy (CT), and radiation therapy (RT). The primary end point was overall survival (OS); the secondary end points included tumor complete response rates, patterns of failure, and toxicity. Kaplan-Meier curves were compared with the log-rank test. Univariate and multivariate analyses were used to determine prognosticators for OS. RESULTS: A total of 72 patients were included in the analysis: 24 (33%) from our hospital and 48 (67%) from the literature. The median OS of all patients was 15.0 months. Patients who received CT had a significantly longer median OS than did those who did not (OS 22.8 months vs 10.0 months) (P=0.03). Patients treated with multimodality therapy (including RT+CT [18%], S+CT [40%], or S+RT+CT [17%]) vs monotherapy (typically, S [18%]) had significantly improved OS (15.5 months vs 9.3 months) (P=0.02) and complete response rates. On multivariate analysis, tumor location (upper third of the esophagus) and type of treatment (monotherapy) were the only factors predictive of poor OS. CONCLUSION: Multimodality therapy (including RT+CT, S+CT, or S+RT+CT) improves OS for patients with LS-C-SCEC compared with monotherapy (typically, S). Additional studies are necessary to personalize multimodal treatment approaches to individual patients.

DNA repair gene polymorphisms and clinical outcome of patients with primary small cell carcinoma of the esophagus.

Polymorphisms in DNA repair genes impact on the synthesis of DNA repair proteins that are crucial to the repair of DNA damages induced by chemotherapy and radiotherapy. We retrospectively examined whether there was an association between the selected six single nucleotide polymorphisms (SNPs) of five DNA repair genes (PARP1-Val762Ala, XRCC1-Arg194Trp, XRCC1-Arg399Gln, XPC-Lys939Gln, BRCA1-Lys1183Arg, and BRCA2-Asn372His) and the clinical outcome of patients with primary small cell carcinoma of esophagus (SCCE), and it showed that the median progression-free survival (PFS) and the overall survival (OS) were 11.8 versus 9.7 months (P = 0.041) and 17.4 versus 14.8 months (P = 0.032) for patients carrying the variant allele (T/C + C/C) and the wild-type allele (T/T) of PARP1-Val762Ala polymorphism, respectively. However, no statistical significance was observed in the other five polymorphic loci (P > 0.05). When these six SNPs were combined, however, patients with at least three variant genotypes had significantly longer PFS and OS compared with those carrying less than three variant genotypes (P = 0.009 and P = 0.007, respectively). The presence of at least three polymorphic variants in certain DNA repair genes may impact on patient survival and could be a potential genomic predictor of clinical response to DNA-damaging treatment in SCCE patients.

Targeting pyruvate kinase M2 contributes to radiosensitivity of non-small cell lung cancer cells in vitro and in vivo.

Aerobic glycolysis, a metabolic hallmark of cancer, is associated with radioresistance in non-small cell lung cancer (NSCLC). Pyruvate kinase M2 isoform (PKM2), a key regulator of glycolysis, is expressed exclusively in cancers. However, the impact of PKM2 silencing on the radiosensitivity of NSCLC has not been explored. Here, we show a plasmid of shRNA-PKM2 for expressing a short hairpin RNA targeting PKM2 (pshRNA-PKM2) and demonstrate that treatment with pshRNA-PKM2 effectively inhibits PKM2 expression in NSCLC cell lines and xenografts. Silencing of PKM2 expression enhanced ionizing radiation (IR)-induced apoptosis and autophagy in vitro and in vivo, accompanied by inhibiting AKT and PDK1 phosphorylation, but enhanced ERK and GSK3ß phosphorylation. These results demonstrated that knockdown of PKM2 expression enhances the radiosensitivity of NSCLC cell lines and xenografts as well as may aid in the design of new therapies for the treatment of NSCLC.